1. Field of the Invention
An aspect of the present invention relates to a cylinder type lithium ion secondary battery.
2. Description of the Related Art
In general, lithium secondary batteries, which can be repeatedly recharged and can be made in a small size while having a large capacity, are widely used in advanced electronic devices because of various advantages, including a high operation voltage, a high energy density per unit weight, and so forth.
The lithium secondary batteries are largely classified as cylinder type secondary batteries and prismatic type secondary batteries. The cylinder type lithium secondary battery includes a cylindrical electrode assembly to which a center pin is coupled to the electrode assembly, a cylindrical can accommodating the electrode assembly, an electrolyte injected into the can to allow movement of lithium ions, and a cap assembly coupled to one side of the can to prevent leakage of the electrolyte and separation of the electrode assembly.